In PTL 1, a catheter is described which includes a tubular body provided with a lumen (sub-lumen) and an operating wire slidably inserted into the sub-lumen, and is configured such that the tubular body is bent by pulling the operating wire. The operating wire in the literature is a stranded wire formed by stranding a plurality of thin wires together, and in order to enhance the slidability of the operating wire, the surface of the stranded wire is hydrophobized. The hydrophobization is realized by forming a hydrophobic resin layer on the surface of the stranded wire.